Which of the property was used by Mendeleev to classify the elements ?
1. Brightness
2. Atomic weight or mass
3. Number of isotopes
4. Lustre

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| List-I (IUPAC official name) |
List-II (IUPAC Symbol) |
||
| A. | Mendelevium | I. | Mt |
| B. | Meitnerium | II. | Mc |
| C. | Moscovium | III. | No |
| D. | Nobelium | IV. | Md |
| 1. | A-III, B-I, C-II, D-IV | 2. | A-IV, B-II, C-I, D-III |
| 3. | A-IV, B-I, C-II, D-III | 4. | A-I, B-IV, C-II, D-III |

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The group number, number of valence electrons, and valency of an element with atomic number 15,
respectively, are:
1. 16, 6 and 3
2. 15, 6 and 12
3. 16, 5 and 2
4. 15, 5 and 3
Among the following, the elements that can show covalency greater than 4 is/are:
(a) Be
(b) P
(c) S
(d) B
Choose the correct option
1. (a), (d)
2. (b), (c)
3. (c), (d)
4. (b), (d)

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Match the elements in Column I with their corresponding types in Column II.
| Column I | Column II | ||
| (a) | Copper | (i) | Non-metal |
| (b) | Fluorine | (ii) | Transition metal |
| (c) | Silicon | (iii) | Lanthanoid |
| (d) | Cerium | (iv) | Metalloid |
Identify the correct match:
1. (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)
2. (a)-(ii), (b)-(i), (c)-(iv), (d)-(iii)
3. (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
4. (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)